Level marking method and level marking apparatus

ABSTRACT

A level marking method including providing a hose having a first end and a second end; filling the hose, at least partially, with a liquid so as to form a water head; leaving the first end of the hose open to atmospheric pressure; closing the second end of the hose by airtightly fixing a pressure sensor to the second end of the hose near the water head; connecting a solenoid inker having an inking level to the pressure sensor, said solenoid inker being operated by ON and OFF signals dispatched from the pressure sensor and automatically drawing a mark at the inking level when it operates; configuring the hose so as to define a reference level by obtaining a reference level pressure value from the pressure sensor; arranging said pressure sensor such that it dispatches an ON signal at the reference level, and dispatches an OFF signal otherwise; and marking the level by vertically displacing the second end of the hose so as to cause the pressure sensor to dispatch an ON signal.

BACKGROUND OF THE INVENTION

As an example of a level position measuring means, there has been suchtype that is a combination of a staff and an optical-type level readsthe scale of the staff. This type of means has a disadvantage that thescale of the staff is misread. The measurement with this type of meansis completed such that the staff is positioned at a certain distance,and the scale of the staff is read both from the front and the backthereof, then an inking is done manually. The same operation is repeateda number of times. Therefore, other than the measurer who actually readsthe scale, an extra person is required, but still the misread of thescale cannot be avoided. Because of such reasons, a means which canautomaticaly perform accurate measurement without relying much on humanbeings is desirable.

For this purpose, in the past, there is apparatus where a laser beam isemitted from a level to a staff, reading the scale of the staff.However, in this prior art, a spot of the laser beam on the staff israther big, so that it lacks an accuracy of the measurement. Further,another problem of this prior art is that the operator of the levelcannot read the scale of the level.

In both optical-type level and laser-type level, there is suchdisadvantage that an marking has to be done manually relying on humaneyes, so that an accuracy of the measurement is unreliable. Further,both means can be applied only on such place that visibility thereof isgood. When they are to be applied, for example, on depressed area or aplace with obstacles, the levels have to be moved to obtain a goodvisibility, which became a cause of unacourate measurement.

A level position measuring means in such cases that a room, for example,is so small that a level cannot be used therein and that an accuracy ofthe measurement is not highly required, a leveling tube, which is asimple tool for measuring a level position, is employed. The levelingtubes are only used by craftsmen and for smaller scale of constructions,but an extent of utilization thereof is still high.

The leveling tube mentioned above is shown in FIG. 5. The leveling tubeis arranged such that a rubber hose 3 is connected to the bottom of awater container 2, which is transparent so that the water head 1 can beseen outside thereof, and a glass tube 4 is connected to the edge of therubber hose 3. The level 6 of the water 5 is stable, so that the waterhead 7 of the glass tube 4 positions to the level equal to the waterhead 1 of the water container 2, the reference level.

For smaller constructions, the leveling tube, which does not require anexpensive level, is effectively used. However, it has such problems thatit takes time until the water level stablizes because of the fluidity ofthe water in the hose, and that the results of level measuring variesdepending on the reader because the water level in the glass tube formsdepression because of the surface tension thereof, so that theefficiency and the accuracy of the measurement thereof areunsatisfactory.

The object of the present invention, therefore, is to provide a meansfor level position measuring comprising a hose, which preventsmisreading of measurement.

According to the prior art, marking is done manually relying on humaneyes, so that the marking lacks accuracy. Therefore, another object ofthe present invention is to provide a means for marking which resolvessuch problem.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a basic structure of the present invention.

FIG. 2 shows a level marking apparatus according to the presentinvention.

FIG. 3a shows a side elevational view of the staff plate portion of alevel marking apparatus having an automatic temperature compensatingfunction according to the present invention.

FIG. 3b shows a elevational view of the apparatus shown in FIG. 3a.

FIG. 4 shows a elevational view of the other side (the reference levelportion) of a level marking apparatus having an automatic temperaturecompensating function according to the present invention.

FIG. 5 shows a leveling tube as a prior art.

FIG. 6a shows an apparatus comprising a temperature compensationfunction according to the present invention.

FIG. 6b shows the apparatus of FIG. 6a at a lower temperature.

FIG. 6c shows the apparatus of FIG. 6a at a higher temperature.

THE DETAILED DESCRIPTION OF THE INVENTION

To acquire the objects described above, a level position measuringmethod according to the present invention is such that one end of a hoseis opened while the the other end thereof is airtightly closed, liquidsuch as water is filled in the hose, and a pressure sensor is attachedto the closed end of the hose. When a water level of the open end of thehose is determined the reference level, while the pressure sensor beingpositioned equal to the reference level, the pressure of the pressuresensor is zero, while the sensor being positioned below the referencelevel, proportioned positive pressure applies to the sensor, and on theother hand, while the sensor being positioned higher than the referencelevel, proportioned negative pressure applies to the sensor. Such theoryis applied for measuring a level according to the present invention.

A level marking method according to the present invention is such thatthe pressure sensor applied to the level position measuring methoddescribed above is connected to a solenoid-type inker which functions byON and OFF electric signals dispatched from the sensor. The ON/OFFsignals are arranged such that when a marking level of the solenoid-typeinker and the water level of the opened end of the hose are at the samelevel, the ON singnal is dispatched, while other than such conditions,the OFF signal is dispatched, and by leveling the water level of theopened end of the hose to the reference level, a marking can be appliedautomatically at a level equal to the reference level.

A level marking apparatus according to the present invention is suchthat the closed end of the hose is fixed to a staff plate which isarranged to move up and down on a surface a marking is to be placed, andthe staff plate is provided with the solenoid-type inker which isconnected to the pressure sensor, and the pressure sensor is arrangedsuch that it dispatches an ON signal when the level of the marker equalsto the water level of the open end of the hose, and that it dispatchesan OFF signal when the level of the marker is not equal to the waterlevel of the open end of the hose. The open end of the hose according tothis apparatus can be firmly fixed to a plate having a mark indicatingthe reference level.

To prevent inaccuracy in measurement caused by variations oftemperature, a level marking apparatus according to the presentinvention comprises a hose for temperature compensation. The hose fortemperature compensation is such that the quality of the materialthereof, the length thereof, the diameter thereof and the liquid filledtherein are arranged similar to those of the regular hose mentionedpreviously, and one end thereof is opened while the other end is airtightly closed. The hose for temperature compensation is attached to theregular hose as such that the open end of the former one is positionedby the open end of the latter one. The open end of the hose fortemperature compensation is provided with a piston therein, which isfirmly fixed to a plate, arranging the open end airtightly closed by thepiston, and the both hoses supported capable of moving toward thepiston.

A level marking apparatus according to the present invention functionsas such that the water level of the open end of the hose is leveled tothe reference level, and the closed end of the hose is moved upwardly ordownwardly on a wall or the like on which marking is to be done. Thepressure sensor perceives negative pressure while it positions above thereference level, positive pressure while it is below the reference leveland zero at the equal level, so that, with this theory, a level markingcan be done.

The solenoid-type inker mentioned previously, which is connected to thepressure sensor and performs marking automatically, is such that even ifthe marking level thereof is unequal to the level of the pressuresensor, such unequality can be adjusted by arranging the sensor todispatch a signal by compensation, so that the inker can apply a markingto a level equal to the reference level. The pressure sensor is arrangedsuch that it dispatches an ON signal when it is at a level equal to thereference level, and that it dispatches an OFF signal when it is loweror higher than the reference level, so that an automatic marking can beperformed.

The volume of the hose and the water therein vary because of variationsof temperature. In such case, the water head of the opening end of thehose does not come to the level equal to the line, the reference level,marked on the plate. To prevent such phenomenon, a hose for a automatictemperature compensation can be attached unitedly to the hose, makingthem a double-hose. And by fixing the staff plate side unmovable andarranging the other side movable, the water level of the opening end ofthe hose for temperature compensation, which is the under surface of thepiston, can be stabilized as a fixed point, so that the water head ofthe opening end of the hose can be automatically leveled equal to thereference level.

PREFERRED EMBODIMENT OF THE INVENTION

A preferred embodiment according to the present invention will bedescribed below referring to the drawings. In FIG. 1 , a hose 8 with acertain length is such that one end 8a thereof is open and the other end8b thereof is airtightly closed by a pressure sensor 9. The hose isfilled with liquid 10 such as water.

The one end 8a is firmly secured, determining the water level thereofthe reference level 11, and the other end 8b is moved in the verticaldirections, then the pressure sensor 9 functions as such that when waterhead of the other end 8b of the hose is at a lower level 12 than thereference level 11, it perceives positive pressure, that when it is at ahigher level 13, it perceives negative pressure, and that when it is ata equal level 14, it perceives no pressure.

According to the strength of the pressure the sensor perceives, adistance to the reference level can be obtained. The easiest way to makemarking is such that the water level of the other end 8b is determinedas the marking level, and when the water level comes to a level equal tothe reference level, the pressure sensor perceives zero pressure anddispatches a signal to make a marking. The signal is dispatched in aninstant, so that one does not have to wait until a water level becomestablized to be read as in a prior art.

The pressure sensor 9 is sensitive against a change of the pressure, sothat it is effective to correctly measure a level.

In FIG. 2, the apparatus is provided with a solenoid-type inker 15,which functions by ON and OFF electric signals dispatched from thepressure sensor 9. The pressure sensor 9 and the inker 15 are secured toa staff plate 17, which comprises rollers 16. The ON signal isdispatched when the marking level 18 and the reference level 11, whichis the water head level of one end 8a of the hose 8, come to the samelevel, and the OFF signal is dispatched in other conditions.

As shown in FIG. 2, when there is some level gap L between the markinglevel 18 and the water head of one end 8b of the hose, some compensationcan be applied to remove the gap. Therefore, as the other end 8b of thehose is moved up and down on a surface of a wall or the like, a markingis instantly done on the wall or the like. This removes an individualdifference in marking, improves total accuracy in measuring and enablesa single person to complete the marking in a shorter time.

As mentioned above, the water head of one end 8a of the hose should beleveled equal to the reference level 11. To make this easier, it isrecommended that the plate 19 comprises a line thereon and adjust thewater head of the one end 8a of the hose to the line.

As shown in FIGS. 3(a), 3(b) and 4, a hose 20 for an automatictemperature compensation, the material, length and diameter thereof aresimilar to the hose 8, and the liquid filled therein is also similar tothe one filled in the hose 8, is unitedly fixed to the hose 8, attachingthe closed side 20b of the of the hose 20 to the edge portion 8b of thehose 8, making them a double-hose.

In the opening end 20a of the hose 20, a piston 21 which is fixed to theplate 19 is inserted airtightly.

The opening ends 8a, 20a of the hoses 8, 20 are held capable of movingto the plate 19 with a holder 22, and they are also held and pulled inthe direction of the piston 21 side by springs 23.

The water level of the opening end 20a of the hose 20 always makecontact with the under surface of the piston 21. The means comprises alid 24 which closes an end portion 8a of the hose 8, a battery 25 for asolenoid inker 15 placed on the staff plate 19.

The staff plate 17 side is arranged as a fixed side and the other plate19 side is arranged as a movable side, so that the volume variations ofthe liquid 10 caused by the temperature variation is absorbed andadjusted as the hose 20 moves at the movable side.

The hose 8 moves with the hose 20 because they are fixed unitedly, andthe level of the water head of the liquid 10 in the hose 8 is similar tothe level of the liquid 10 in the the hose 20. Therefore, the waterheads of the liquid in the hoses 8, 20 always come to the level equal tothe reference level 11 marked on the plate 19 as the hoses 8, 20 moveupward and downward depending on the temperature performing automatictemperature compensation.

This phenomenon will be further described below referring FIG. 6. Thisdrawing discloses a means in which an opening end 20a of the hose 20 isarranged as a cylinder and one end 8a of the hose 8 is also arranged asa cylinder, and a float 26 is placed in the cylinder 8, and the lid 24with a vertical hole therethrough is secured to the cylinder 8. FIG.6(a) shows a condition of normal temperature. FIG. 6(b) shows acondition of lower temperature, wherein the cylinder moves upward as theliquid 10 in the cylinder and hose contracts because of the temperaturedecrease. As the temperature increases, as shown in FIG. 6(c), thecylinder moves downward because the liquid 10 in the cylinder and thehose expands.

It should be clearly noted, that the piston 21 is firmly fixed, so thatthe function mentioned above is performed and that the water level (thebottom surface of the piston 21) becomes immovable point.

Therefore, according to such means, it is not necessary to arrange thewater head of the hose 8 equal to the reference level prior to its use.

It is preferable, as shown in FIG. 3b, that the pressure sensor 9comprises a button 9a for zero-point compensation to dispatch ON signalwhen the reference level 11 of the staff plate 17 is adjusted with thereference level 11 of the plate 19.

The present invention comprises such effects mentioned below.

The leveling can be performed by a pressure sensor, so that it can becompleted quickly without any errors. By including the solenoid inker tothe pressure sensor, the inking can be automatically performed withouterrors. The present invention can be used by a single person at anyplace such, as where visibility is bad.

I claim:
 1. A level marking method comprising:providing a hose having afirst end and a second end; filling the hose, at least partially, with aliquid so as to form a water head; leaving the first end of the hoseopen to atmospheric pressure; closing the second end of the hose byairtightly fixing a pressure sensor to the second end of the hose nearthe water head; connecting a solenoid inker having an inking level tothe pressure sensor, said solenoid inker being operated by ON and OFFsignals dispatched from the pressure sensor and automatically drawing amark at the inking level when it operates; configuring the hose so as todefine a reference level by obtaining a reference level pressure valuefrom the pressure sensor; arranging said pressure sensor such that isdispatches an ON signal at the reference level, and dispatches an OFFsignal otherwise; and marking the level by vertically displacing thesecond end of the hose so as to cause the pressure sensor to dispatch anON signal.
 2. A level marking apparatus comprising:a hose having a firstend and a second end, said hose being filled at least partially with aliquid so as to form a water head, wherein the first end of the hose isopen to atmospheric pressure; a pressure sensor airtightly fixed to thesecond end of the hose near the water head so as to close said secondend of the hose; a staff plate on which the second end of the hose isfirmly secured, said staff plate being capable of being verticallydisplaced beside a surface to which a marking is to be applied so as todefine a reference level; and a solenoid inker having an inking levelsecured on the staff plate and connected to the pressure sensor, saidsolenoid inker being operated by ON and OFF signals dispatched from thepressure sensor and automatically drawing a mark at the inking levelwhen it operates, wherein said pressure sensor is arranged to dispatchan ON signal, to the solenoid inker at the reference level, and dispatchan OFF signal otherwise.
 3. The level marking apparatus of claim 2,wherein the open first end of the hose is firmly secured to the secondplate having an adjustable visible line to indicate the reference level.4. A level marking apparatus comprising:a first hose having a first endand a second end, said first hose being filled at least partially with aliquid so as to form a water head, wherein the first end of the firsthose is open to atmospheric pressure; a pressure sensor airtightly fixedto the second end of the first hose near the water head so as to closesaid second end of the first hose; a staff plate on which the second endof the first hose is firmly secured, said staff plate being capable ofbeing vertically displaced beside a surface to which a marking is to beapplied so as to define a reference level; a solenoid inker having aninker level secured on the staff plate and connected to the pressuresensor, said solenoid inker being operated by ON and OFF signalsdispatched from the pressure sensor and automatically drawing a mark atthe inker level when it operates, wherein said pressure sensor isarranged to dispatch an ON signal, to the solenoid inker at thereference level, and dispatch an OFF signal otherwise; a second hose,for temperature compensation, made of a material, and having a lengthand an internal diameter, similar to the first hose, said second hosehaving a first end and a second end, the second end of the second hosebeing airtightly closed, said second hose being filled with the sameliquid as the first hose, said first end of said second hose beingsecured said first end of said first hose in such manner that the firstend of the first hose is parallel to the first end of the second hose;and a piston inserted into the first end of the second hose, said pistonbeing attached to the staff plate.